It allows to use 12g or 33g (33g co2 adaptor included) CO2 capsules. Adapters are designed to work with Mancraft HRR Regulators. It can by use with regulators from other companies but they must have R 1/2" thread in their products (Paintball standard).
The standard 12g capsules - for SDIK conversion kit - lets give around 40-70 shots - depending on the pressure settings.
Multistage expansion chamber prevents liquid co2 from going to the regulator.
Piercing: a classic cone with hole.